Bangladesh cyclone kills six

Cyclone Mahasen bears down on Bangladesh's low-lying coast on Thursday.

Winds of up to 100 kilometres per hour lashed the coast and whipped up waves.

Media reports said five people were killed, some by falling trees, and thousands of rickety huts were destroyed as the storm brought torrential rains.

An expected 2.1 metre storm surge and heavy rain is likely to cause widespread flooding.

About 1 million people had been moved from coastal areas into shelters.

The United Nations says the cyclone threatens 4.1 million people.

Storms in the past have killed many people in Bangladesh.

The country has more than 1,400 cyclone-proof buildings where people moved into for safety.